Bridging Heritage Conservation and Energy Efficiency: Retrofitting Historic Social Housing in Mediterranean Cities

Historic social housing in Mediterranean cities faces the dual challenges of energy inefficiency and cultural preservation. This study presents a pilot methodological framework for energy retrofitting of historical residence buildings, using the Kaisariani Asia Minor refugee housing complex in Athens as a case study. A bibliometric analysis revealed a research gap, as clusters concerning heritage retrofitting and social housing remain weakly connected, highlighting limited interdisciplinary integration between cultural conservation and energy-efficient design. The proposed framework combines historical analysis, energy consumption assessment, and technical evaluation to examine three retrofit scenarios that integrate thermal insulation, upgraded HVAC systems, renewable domestic hot water, and photovoltaic installations. Results demonstrate that substantial performance improvements can be achieved without compromising architectural authenticity. The most comprehensive scenario achieved a 97% reduction in primary energy demand, a 63–76% decrease in heating and cooling loads, and significant CO2 emission reductions, maintaining economic feasibility with a payback period of approximately ten years. The findings emphasize that conservation-compatible retrofitting can transform obsolete housing into low-energy buildings, fostering environmental, social, and cultural sustainability. Beyond quantitative energy gains, the study underlines the importance of integrating heritage values and community identity into urban regeneration strategies, offering a transferable model for Mediterranean municipalities seeking to align climate action with cultural continuity.